1. Field of the Invention
The present invention relates to a semiconductor device using a TAB (tape automated bonding) technique and, more particularly, to a TAB tape capable of coping with mounting on various types of packages and printed circuit boards.
2. Description of the Related Art
In a TAB semiconductor device (TAB package), the resistance or inductance at a lead or bonding portion must be minimized, so that a lead such as a power supply and grounding lead which requires a large current is formed wider than a normal signal lead. That is, leads having a normal width and wider leads are fixed together on a TAB tape. When a device is to be mounted on a large package such as a PGA (pin grid array) by using this TAB package, outer leads of the TAB tape are connected to wiring patterns in the PGA package by the single point bonding method. At this time, the bonding conditions are different depending on lead widths. For this reason, bonding tools must be exchanged, or the bonding process is prolonged.
An arrangement to solve the above problem is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2-295143. According to this arrangement, the wider leads are divided at the bonding portions to have the same width as the normal leads. The same bonding conditions are thus obtained to make gang bonding possible.
The arrangement in the above prior art is as follows. Normal signal leads and wider leads are formed together on a TAB tape. The wider leads are divided at specific portions, where they are bonded with the internal terminals of a PGA package, to have the same width as the normal signal leads. Making the lead width uniform, the same bonding conditions can be obtained.
With the above arrangement, however, the wider leads remain wider in a device hole region. The device hole is a region where the leads are present without being supported by the TAB tape. In this region, the user cuts the leads of the TAB tape at an arbitrary length in mounting. If gang bonding is desired, the user must cut the leads while avoiding the portions where the wider leads are formed in the device hole region. Therefore, this arrangement poses a limit on free mounting by the user and does not cope with mounting in a wide range.